KR0174075B1 - Signal transmission module of sound counter system - Google Patents

Abstract

The present invention is a signal transmission module for transmitting the signal received from the acoustic module (Acoustic Module) in the acoustic counter measure (Acoustic Counter Measure) to detect the acoustic signal in the water to detect the exact position of the sound source, etc. (Telemetry Data Moudle).

The signal transmission module of the present invention is largely composed of three groups consisting of an analog multiplexer part and a digital multiplexer / driver part. The analog multiplexer part converts a received current type signal into a voltage type signal and converts the signal into a constant frequency (for example, 15.36). Sampling and multiplexing at intervals of KHz), 32-channel acoustic sensor signals are amplified by 20dB, and 4-channel auxiliary sensor signals are output to the digital multiplexer / driver section without amplification.The digital multiplexer / driver section outputs signals transmitted from the analog multiplexer section. After converting to 12-bit digital signal and digitally multiplexing and inserting frame signal and inverted frame signal which distinguish each group signal and 36 channel signal in the group alternately at the beginning of channel data, Defined manner (e.g. HD) to facilitate detection and calibration B3, AMI) and converts the line-coded unipolar signal into a bipolar signal, which is advantageous for transmission lines, and then distorts the signal by transmitting only the power with coarse cable with the signal level intact to prevent the loss caused during signal transmission. Remote transmission is possible without.

Description

Signal transmission module of sound counter system

FIG. 1 is a block diagram of an expected configuration of the acoustic countermeasure system.

2 is a block diagram showing in detail the vibration isolation module and the sound module of FIG.

3 is a block diagram of the signal transmission module of the present invention.

4 is a block diagram showing in detail the analog multiplexer of FIG.

5 is a block diagram showing in detail the digital multiplexer / driver of FIG.

* Explanation of symbols for main parts of the drawings

100: ship 110: data processing unit

120: signal receiver 200: towing cable

300: sound sensor unit 310: vibration isolation module

311: tension sensor 312: buffer

320: signal transmission module 321A, 321B, 321C: analog multiplexer

322A, 322B, 322C: Digital Multiplexer / Driver Section

330: sound module 331: hydrophone

332: preamplifier 333: protection circuit

334 Seawater noise compensation circuit 335,336 Roll sensor

337: depth sensor 338: orientation sensor

340: tail rope assembly

The present invention samples the signals transmitted from an acoustic module of an acoustic counter measure that detects the sound of the water and detects the exact position of the sound source, and converts the analog / digital conversion and multiplexes the converted signal. It relates to a signal transmission module (Telemetry Data Module) for long-distance transmission without distortion of the signal.

In general, the acoustic countermeasure system that detects the acoustic signal in the water and detects the exact location of the sound source detects the acoustic wave, which is fixed to the vessel to install the acoustic sensor unit on the vessel and subsea to the acoustic sensor installed on the sea floor; There is a towing doll that is connected to the ship by a towing cable.

The towed acoustic counter module (Towed Acoustic Counter Module) detects the acoustic signal in the water as shown in FIG. 1 and converts it into an electrical analog signal and converts it back into a digital signal and multiplexed to the signal receiver 120 A towing cable 200 for connecting the acoustic sensor unit 300 to be transmitted, the acoustic sensor unit 300 in the ship and the underwater, and the electrical signal received from the acoustic sensor unit 300 data processing unit in the vessel 100 The signal receiver 120 and the data processor 110 for classifying, searching, and processing the signal data received from the signal receiver 120 are provided.

In addition, the acoustic sensor unit 300 includes a vibration isolation module 310 for attenuating initial vibration, a signal transmission module 320 for converting an input analog signal into a digital signal, and transmitting an acoustic signal. A sound module 330, and the tail rope assembly 340 to attenuate the vibration finally.

Hereinafter, the operation of the acoustic sensor unit 300 will be described in detail with reference to FIG. 2.

The acoustic module 330 is a module that receives sea sound signals and converts them into electrical signals and removes seawater noise flowing through the signals. Hydrophone: 331, a preamplifier (Pre-Amp: 332) for amplifying a fine signal, a protection circuit (Input Protector: 333) to protect the hydrophone 331 from overcurrent, and the tilt of the acoustic sensor unit 330 Roll sensor (335,336) for detecting the load, Sea Noise Correction Amp (334) for compensating for noise caused by sea water, and depth sensor (337) for measuring the depth of the acoustic sensor unit 330 And an orientation sensor 338 for measuring the orientation of the acoustic sensor unit 330.

The hydrophone 331 and the preamplifier 332 have three groups in one package at intervals of 120 °, and since these packages are arranged in 32, each group has 32 channels.

Underwater acoustics are propagated by the mechanical coarse action of seawater particles, and the vibration causes a volume change in the hydrophone 331 with a magnitude proportional to the product of the square of the frequency and amplitude, thereby causing the hydrophone 331 to transmit an electrical energy signal. Occurs.

The electrical energy signal is expressed in the form of current and voltage. Impedance coupling considering the sensitivity with the output preamplifier 332 of the hydrophone 331 may transmit the signal of the hydrophone 331 farther.

The preamplifier 332 amplifies the weak signal of the output terminal of the hydrophone 331, and processes the small signal of the hydrophone 331 after an emphasis process to compensate for the attenuation according to the progress of the sound wave. Amplify easily.

The emphasis refers to a pre-emphasis that changes a signal to generate a high frequency spread and a de-emphasis that extends a low frequency component as compared to a high frequency. Signal To Noise Ratio (SNR) is increased.

In more detail, a signal in which most energy exists in a low frequency region such as sound waves does not cause a large frequency deviation due to a high frequency component of the same magnitude.

Therefore, the energy of the signal is not uniformly distributed over the allocated bandwidth, but the energy of the high frequency portion is less distributed, which results in a weak signal-to-noise ratio for the high frequency signal.

Pre-emphasis and de-emphasis methods to overcome these weaknesses have high signal level and noise can be suppressed to some extent in the transmitter, so the signal to be modulated is intentionally extended by high frequency compared to low frequency. In the receiver, the signal level is high and the noise can be suppressed to some extent so that the signal to be demodulated is intentionally changed by extending the low frequency compared to the high frequency.

When the signal is amplified by the preamplifier 332, the noise is also amplified together in the signal, thereby limiting the amplification circuit bandwidth of the preamplifier 332 in consideration of the removal of the noise factor itself as well as the surrounding noise. It is decreasing.

The amplification element itself includes noise generated by the amplifying element, 1 / f noise, shot noise, and Johnson noise, which occur in the low pass filter frequency band, and 1 / f noise occurs in the low pass band, and Johnson noise, Shot noise is called white noise because it appears above the frequency modulation band and is uniformly distributed in the frequency band.

As the signal processed as described above passes through the sea noise compensation circuit 334, the noise signal in the sea water existing in the low frequency region is blocked, and the attenuated high frequency component signal is compensated and transmitted to the signal transmission module 320.

In addition, the depth sensor 337 and the azimuth sensor 338 of the acoustic module 330 measure azimuth and depth information, which are examples of the acoustic sensor unit 300, and transmit the measured azimuth and depth information to the signal transmission module 320.

An object of the present invention is to provide a signal transmission module for sampling the signals received from the sound module to analog-digital conversion and multiplexing the converted signal to remotely transmit the signal without distortion.

Referring to the configuration of the present invention with reference to FIGS. 3 to 5 as follows.

The signal transmission module 320 of the present invention is divided into three groups A, B, and C, and each group has an analog multiplexer unit 321A, 321B, and 321C having a 36-channel input, and a digital multiplexer / driver unit 322A and 322B. 322C).

In addition, the analog multiplexer unit 321A, 321B, and 321C are current / voltage conversion means for converting 32 analog sound sensor signals and 4 auxiliary sensor signals transmitted in a current form from the acoustic module 330 into voltage forms (I / V CONV) and the analog multiplexer (AMUX) that samples and multiplexes the sensor signal at a constant frequency (e.g. 15.36KHz) using the control signals of the digital multiplexer / drivers 322A, 322B, and 322C. Acoustic sensor signal is amplified 20dB and 4 channels of auxiliary sensor signal is composed of gain amplification means (Gain Amp) to output without amplification,

The digital multiplexer / driver unit 322A, 322B, and 322C generates a timing signal for analog multiplexing and sampling a 36-channel signal and generates three CA signals and six GR signals used as control signals. EPLD2 (Erasable Programmable), which provides a conversion signal and generates a frame time slot (Data Interval) for the analog-to-digital converter (A / D CON) to convert the analog signal into a digital signal. Logic Device 2: an analog / digital converter that receives a signal output through the gain amplification means (Gain Amp) of the erase / programmable logic element) and the analog multiplexer unit 321A, 321B, and 321C. (A / D CON) and Data Latch to store signals for converting converted signals into parallel digital signals and 12: 1 parallel data Digital multiplexer (MUX) for multiplexing and outputting serial data, frame aliment signal (FAS) and inverted frame signal (FAX inversion) that distinguish each group signal and 36 channel signals in group EPLD1 consisting of a FAS multiplexer (FAS MUX) and a line coder (Line Coder) coding in a predetermined manner (e.g., HDB3) to facilitate detection and correction of errors occurring during data transmission, and a line coded unipolar signal. Unipolar / bipolar conversion means (U / B CONV) for converting the signal into a bipolar signal in favor of the transmission line, and a line driver (LDRV) that increases power with the signal level intact in order to prevent loss caused during signal transmission before transmission. And A and C include a clock receiver (CLK REV) and a group B includes a clock generator (CLK GEN) to provide a synchronous clock for simultaneously processing three groups of data. The.

Referring to the operation and effects of the present invention with reference to FIGS. 3 to 5 as follows.

3 is a block diagram showing the configuration of the signal transmission module of the present invention, and FIG. 4 is a block diagram showing the analog multiplexer part of the signal transmission module of the present invention in detail. FIG. 5 is a detailed view of the digital multiplexer / driver unit of the signal transmission module of the present invention. A block diagram is shown.

When 32 analog sound sensor signals and 4 auxiliary sensor signals transmitted from the sound module 330 in the current form are input to each of the groups A, B, and C of the signal transmission module, the current form signal is a current / voltage converting means (I / V CONV) is converted into a voltage form and the analog multiplexer (AMUX) uses the GR and CA signals generated by EPLD2 of the digital multiplexer / drivers 332A, 322B, and 322C as control signals, and uses the converted signal at a constant frequency. Sampling and multiplexing at intervals of 15.36KHz are then output to the gain amplifier.

The gain amplification means Gain Amp amplifies 20 dB of the 32-channel (CH1-CH32) acoustic sensor signals from the signals sequentially output from the analog multiplexer (AMUX) and the auxiliary sensor signals of the 4-channel (CH33-CH36) without amplification. Output to the analog-to-digital converters (A / D CON) of the digital multiplexer / driver section 322A, 322B, 322C.

The analog-to-digital converter (A / D CON) receives the conversion signal generated by EPLD2 and converts the signal transmitted from the gain amplification unit (Gain Amp) into a 12-bit digital signal and outputs it to EPLD1.

In the EPLD1, a data latch stores a signal to convert an input digital signal into 12-bit parallel data, and the signal converted into 12-bit parallel data is multiplexed into serial data by a digital multiplexer (MUX). In the FAS MUX, a frame signal (FAX) and an inverted frame signal (FAX inversion) that distinguish the 36 channel signals in the group A, B, C and the group are alternately inserted at the beginning of the channel data. In order to facilitate detection and correction of errors occurring during data transmission in the line core, the line cores are coded and output in a predetermined manner (eg, HDB3 and AMI).

Unipolar / bipolar conversion means (U / B CONV) converts a line-coded monopolar signal into a bipolar signal, which is advantageous for the transmission line, and outputs it to the line driver (LDRV). The line driver (LDRV) transmits the signal before transmitting the signal. In order to prevent the loss caused during the operation, the signal level is left as it is and only the power is increased.

The serial data processed as described above is a vibration isolation that buffers the vibration detected in the buffer (Buffer: 312) by detecting the attenuation of vibration generated from the towing cable and the towing cable and the vibration caused by the towing by the tension sensor (3110). The module 310 is transmitted to the signal receiver 120 installed in the ship 100 of the ship via the towing cable 200.

The signal receiver 120 processes the received signals and transmits the received signals to the data processor 110. The data processor 110 processes the received signal data such as classification and search.

The signal transmission of the signal transmission module 320 as described above is performed by the clock receivers CLK REV of the group A and C receiving the synchronous clock generated from the clock generator CLK GEN of the group B. This is achieved by controlling timing signals, control signals, conversion signals, and frame time slots generated by EPLD2.

According to the present invention, the signals received from the sound module can be sampled and properly amplified to analog / digital conversion, multiplexed converted signals, and then line-coded, unipolar / bipolar converted, and line driven, thereby enabling long-distance transmission without distortion of the signal. There is.

Claims (1)

An acoustic sensor signal having a plurality of channels detected by being separated into three groups in the acoustic module 330 of the acoustic sensor unit 300 of the acoustic countermeasure system which detects the underwater sound and detects the exact position of the sound source; An apparatus for transmitting an auxiliary sensor signal of a predetermined channel indicating the depth and azimuth to the ship 100 through a towing cable 200, the current / voltage conversion means for converting the plurality of sensor signals into a signal of the voltage type (I) / V CONV) and an analog multiplexer (AMUX) for sampling, multiplexing and outputting parallel signals from the current / voltage converting means (I / V CONV) based on a control signal, and from the analog multiplexer (AMUX). An analog multiplexer section 321A, 321B, and 321C comprising gain amplification means (Gain Amp) for amplifying and outputting the multiplexed signal; An analog / digital converter (A / D CON) for converting an analog signal from the gain amplification means (Gain Amp) into a digital signal of a predetermined bit based on the conversion signal, and a data latch for storing the converted digital signal. ), A digital multiplexer (MUX) for multiplexing and outputting a latched predetermined bit digital signal, and a frame signal and an inverted frame signal for distinguishing each group and a channel in the group into the multiplexed digital signal are alternately outputted. A FAS multiplexer (FAS MUX), a line coder (Line Coder) coded by a predetermined coding scheme to transmit a signal from the FAS multiplexer (FAS MUX), and a line-coded unipolar signal is converted into a bipolar signal and outputted To amplify the unipolar / bipolar conversion means (U / V CONV) and the power of the bipolar signal and transmit it through the towing cable 200. And a digital multiplexer / driver section 322A, 322B, and 322C comprising a driver LDRV and an erase / programmable logic element section EPLD2 for generating the control and conversion signals and for generating various timing and frame time slots. Signal transmission module of the sound opposing system, characterized in that.